1. Field of the Invention
This invention relates to a printing apparatus for printing data transferred from a plurality of host computers, by way of example.
2. Prior Art
When a plurality of host computers transfer print requests to the same printing apparatus substantially simultaneously in a conventional printing apparatus to which the plurality of host computers are connected, the printing apparatus processes the data from the host computer whose command arrives earliest. The data from another host computer whose print request has not yet been received starts undergoing printing processing following the end of the data processing (printout) executed first. Moreover, even after the data has been transferred to a buffer, the printing apparatus must wait until the end of the data has been detected and only then accepts the data from the host computer issuing the print request. As a consequence, even if the amount of data associated with a print request accepted subsequently is small and immediate printout is required, the length of waiting time is long and the processing efficiency of the overall system composed of the host computers and printing apparatus suffers.
Accordingly, an object of the present invention is to provide a printing apparatus in which data capable of being processed in a short period of time is processed preferentially in a case where print requests are issued simultaneously, thereby making it possible to raise the efficiency of the overall system which prints the data from an information source.
According to the present invention, the foregoing object is attained by providing a printing apparatus connected to a plurality of information sources for printing out data transferred from the information sources, comprising receiving means for receiving data from one of the plurality of information sources, memory means for segmenting the data, which has been received from the receiving means, into blocks of a prescribed size and storing the data block by block, changeover means for changing over the information source whenever one block of data is stored by the memory means, identifying means for identifying the information source of the data that has been stored block by block, and output means for outputting a block of data, which has been identified by the identifying means, from an information source identical with the information source for which reception of the data by the receiving means has ended.
In a preferred embodiment, the memory means decides the size of a stored block based upon the time necessary for reception.
In a preferred embodiment, the memory means decides the size of a stored block based upon the capacity of a memory medium necessary for storage.
In another aspect of the invention, there is provided a printing apparatus connected to a plurality of information sources for printing out data transferred from the information sources, comprising receiving means for receiving the sizes of the data from the information sources in advance, and comparison means for comparing the sizes of the data, wherein data determined to have the smallest size based upon the comparison performed by the comparison means is received and printed out.
Further, according to the present invention, there is provided a printing control method for a printing apparatus connected to a plurality of information sources for printing out data transferred from the information sources, comprising a receiving step of receiving data from one of the plurality of information sources, a storing step of segmenting the data, which has been received at the receiving step, into blocks of a prescribed size and storing the data block by block, a changeover step of changing over the information source whenever one block of data is stored at the storing step, an identifying step of identifying the information source of the data that has been stored block by block, and an output step of outputting a block of data, which has been identified at the identifying step, from an information source identical with the information source for which reception of the data at the receiving step has ended.
Further according to the present invention, there is provided a printing control method for a printing apparatus connected to a plurality of information sources for printing out data transferred from the information sources comprising, a receiving step of receiving the sizes of the data from the information sources in advance and a comparison step of comparing the sizes of the data, wherein data determined to have the smallest size based upon the comparison performed at said comparison step is received and printed out.
Other features and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof.